LM2594/LM2594HV SIMPLE SWITCHER? Power Converter 150 kHz 0.5A
Step-Down Voltage Regulator
General Description
The LM2594/LM2594HV series of regulators are monolithic
integrated circuits that provide all the active functions for a
step-down (buck) switching regulator, capable of driving a
0.5A load with excellent line and load regulation. These devices
are available in fixed output voltages of 3.3V, 5V, 12V,
and an adjustable output version, and are packaged in a
8-lead DIP and a 8-lead surface mount package.
Requiring a minimum number of external components, these
regulators are simple to use and feature internal frequency
compensation?, a fixed-frequency oscillator, and improved
line and load regulation specifications.
The LM2594/LM2594HV series operates at a switching frequency
of 150 kHz thus allowing smaller sized filter components
than what would be needed with lower frequency
switching regulators. Because of its high efficiency, the copper
traces on the printed circuit board are normally the only
heat sinking needed.
A standard series of inductors (both through hole and surface
mount types) are available from several different manufacturers
optimized for use with the LM2594/LM2594HV series.
This feature greatly simplifies the design of
switch-mode power supplies.
Other features include a guaranteed ±4% tolerance on output
voltage under all conditions of input voltage and output
load conditions, and ±15% on the oscillator frequency. External
shutdown is included, featuring typically 85 μA
standby current. Self protection features include a two stage
frequency reducing current limit for the output switch and an
over temperature shutdown for complete protection under
fault conditions.
The LM2594HV is for applications requiring an input voltage
up to 60V.